Pump with by-pass valve



July 28, 1942.

E. F. 'WICHOREK PUMP WIJH BY-lfASS VALVE Filed NOV. 13, 1940 I ZEZfizzazoZFZZ/icvofe "KM Patented July 28, 1942 UNITED STATES PATENTYOFFICE.

PUMP WITH BY-PASS VALVE Edmund F. Wichorek, Cleveland, Ohio, assignor to Pump Engineering Service Corporation, Cleveland, Ohio, a corporation of Ohio 7 Application November 13, 1940, Serial No. 365,529

'3 Claims. (Cl. 103-120) The present invention relates to an improvement in pumps and particularly pumps of the variable displacement type wherein the displacement -is adjusted in accordance with the output pressure and wherein there is provided an arrangement for bypassing fluid from the pump inlet to the pump outlet in response to an auxiliary pressure.

It is the general object of this invention to improve the arrangement and construction of the elements making up the above type of pump whereby to realize increased efficiency in operation and maintenance.

It is a more specific object to so construct a pump of the above type that important elements perform dual functions and thus eliminate the necessity of duplicating parts.

It is a still further object to provide a pump having the above advantages and in addition providing for ready reversal of operation of the pump by the simple interchange of two closure elements.

Other and more particular objects, advantages and uses of my invention will become apparent from'a reading of the following specification taken in connection with the appended drawing which forms a part thereof and wherein:

Fig. 1 is a cross-section of a pump assembly incorporating a preferred embodiment f my invention; and

Fig. 2 is a cross-section taken substantially on the line 2-2 of Fig. 1.

Referring to the figures of the drawing, ID indicates generally a pump incorporating a preferred embodiment of my invention and including essentially ,a variably eccentric adjustable displacement pumping assembly H adapted to draw fuel from inlet [2 and discharge the same from outlet l3; an arrangement of means indicated generally at M adapted to respond to variations in the outlet fluid pressure for adjusting the eccentricity of pumping assembly ll and a bypass assembly indicated generally at I5 for bypassing fluid from the inletv l2 to the outlet l3 around pumping assembly ll.

Certain important elements forming part of the displacement adjustment control means l4 and the bypass assembly I5 perform dual functions in the respective assemblies and it is to this novel arrangement among others that my invention is particularly directed.

Pumping assembly ll may take any one of several well known forms. However, I prefer the general arrangement shown which is described in detail and claimed in Johnson vPatent No.

The bypass assembly I5 is defined in part by a first upstanding-wall 2| forming a nipple-like.

protuberance, a second generally concentric upwardly extending wall 22 spaced radially outwardly from wall 2i and defining an annular bypass chamber therebetween. For the purpose of closing the upper extremities of walls 2| and 22 to thus define a, by-pass chamber 23 as well as to in part define a lower diaphragm chamber 24, I have provided a. novelpartition closure and bearing member indicated generally at 25. This member 25 comprises adownwardly-depending tubular nipple portion 26 externally threaded for reception in engagement with the internal threads of vertical wall 2| and formed internally with a cylindrical bore 21 for substantially tremities of walls 2| and 22 to thus complete the formation of bypass chamber 23 and lower diaphragm chamber 24.

Upwardly extending wall 22 is fbrmed with a first port 3| adapted to be placed imccmmu'nfcation with outlet l3 and a secondgenerally opposed port 32 in communication with the pump inlet. As-will be seen, the inlet and outlet may be reversed.

Arranged for interchangeable cooperation. with the ports 3| and 32 depending upon the desired direction of operation of the pump, I haveprovided a novel valve assembly indicated generally at 34 and including a disc-like valve 35 shown in engagement with port 3|. Extending from the rear face of valve 35 is a hollow tubular pistonlike protuberance 36 arranged to be supported in the cylindrical bore of a removable threaded plug Interposed between the plug and valve .withsame may take the form of an axiallykextending channel bisecting the peripheral thread. n the plug. A pairv of substantially identical housing pas-- sages 41 and 48 have their inner ends communicating with the lower diaphragm chamber 24 s and cylinderfor the reception of said connecting link comprising a member having a centrally depending exterloriy threaded nipple portion threadably received in engagement with complementary threads formed on the inner periphcry of said tubular protuberance, said member .being formed with a cylindrical interior for the reception of said'piston-like link in scalable reciprocable cooperation therewith and further formed with a radially outwardly extending flange Tportion functioning as -a cover for said and their opposite terminals communicating with the housing plug receiving openings 4| and 42 in-- termediate the ends thereof. These terminal portionsof passages 41 and 48 are so disposed that with plug 31 in position with either opening 41 or 42, circular groove or channel 44 will be in communication with the respective terminal end of either passage 41 or 48 thusserving to place the respective port l2 or l3 as the case may be in communication with the underside of the diaphragm for thepurpose of controlling the displacement of the pump assembly Ii in accordance with the discharge pressure. With plug 31 located in o'pening 4| and the pump arranged to operate in a counterclockwise direction, the

opposite opening 42 in the housing adjacent the port 32 is closed by a'blind plug 5 I the peripheral surface portion of which closes the outer terminal of passage 48 leading from the lowerdiaphragm chamber. i

IfWlll be readily apparent that the direction of operation of pump Ill may be quickly changed merely by interchanging valve assembly 34 in cluding plugs 31 with blind plug 5 I;

P/ In addition'to the above there will of course be provided the usual conventional pump elements forming no particular part of the present invention other than in combination, such fifor example as the elements described in greater detail inthe above referred to Johnson patent. ,1

' While I have described my invention in connection with a specific embodiment thereof, it will be understood that this is by way of example only and not by way of limitation, it being intended that my invention be defined solely by the appended claimswhich should be given a scope as broad as commensurate with the prior art. Iclaim:

1. In a variable displacement pump assembly including means defining a housing formed .with a pumping chamber having an inlet port and an outlet portand adapted to'receive a. rotaryadjustable displacement pumping assembly, means responsive to outlet pressure for adjusting the displacement of said pumping assembly including a flexible diaphragm-and connecting pistonlike link means extending between the central portion of said diaphragm and said pumping, assembly, means defining a bypass assembly for bypasslng'fiuid around said pumping;ass'embly from said inlet to said outlet in response to auxiliary fluid pressure, said last named means including a" tubular protuberance extending outwardly from said housing and surrounding said piston-like link, a surrounding wall portion spaced radially from the outer periphery of said tubular protuberance, said wall being formed with a first port in communication with said inincluding means defining a housing formed with let port and a second port opposite said first.port in communication with said outlet port, a combination closure for the upper extremities of saidtubular protuberance and said surrounding wall uppekextremities and defining with portions of said housingswhich are arranged adjacent to said flange portion and with said diaphragm a lower diaphragm, chamber, a -valve assembly including a valve for cooperation witlrsaid second port in said wall, said assembly being characterized by the inclusion of a'first exteriorly threaded plug threadably mounted in a complementariiy formed opening in said housing and provided witha passage therein communicating atone end with said pumpoutlet and having a second terminal por-' tionadjacent the periphery of said plug intermediate the ends thereof normally disposed with-d in the confines of said complementarilyformed opening in said housing, said housing being formed with a passage communicating'at one end with saidlower diaphragm chamber and at the other end with said terminal portion of said passage'in said plug, said plug being formed with a a cylindrical recess forreceiving a piston-like extension protruding from the rear'of said valve.

and a coil compression spring positioned between said plug and said valve for normally urging the latter into engagement with said port with a pre-' determined force dependin u n the adjustment of said plug efiected by turning the same on said thread and a second threaded opening formed in said housing in opposed relation to said first named port, a second passage formed in said housing communicating at one end with said lower diaphragm chamber-and at the other end with said last namedthre'aded opening-"intermediate the ends thereof and asecond threaded plug adapted to be received in said last' named threaded opening and effective to close said second housing passage, said arrangement being such that said threaded plugs may be interchanged for the purpose of maintaining the means responsive to outletpressure and said bypass assembly operative upon reversal of the direction of operation of said pump.

2. The combination defined in claim 1 wherein said first named threaded plug is formed at the outer terminal portion thereof with a radially extending fiange functioning to limit the movernent of said plug inwardly, an annular groove formed about the peripheryof said first plug between said flange portion and the inner terminals portion thereof, said passage formed in said first plug leading from the inner terminal portion thereof to a point in communication with said I annular gro0ve,- saidfirst housing passage arranged to communicate with said annular groove when said plug is in positionwithin said threaded opening 3. In a variable displacement pump assembly a pumping chamber having an inlet, port and an outlet port andadapted to receive a rotary adjustable displacement pumping assembly, means responsive to outletpressure for'adjusting the displacement-of said pumping assembly including a flexible diaphragm and connecting piston-like link means extending between the central portion of said diaphragm and said pumping assembly, means defining a bypass assembly for bypassing fluid around said pumping assembly from said inlet to said outlet in response to auxiliary fluid pressure, said last named means including a tubular protuberance extending outwardly from said housing and surrounding said piston-like link, a surrounding wall portion spaced radially from the outer periphery of said tubular protuberance, said wall being formed with a first port in communication with said inlet port and a second port opposite said first port in communication with said outlet port, a combination closure for the upper extremities of said tubular protuberance and said surrounding wall and cylinder for the reception of said connecting link comprising a member having a centrally depending exteriorly threaded nipple portion threadably received in engagement with complementary threads formed on the inner periphery of said tubular protuberance, said member being formed with a cylindrical interior for the reception of said piston-like link in sealable reciprocable cooperation therewith and further formed EDMUND F. WICHOREK. 

